System and method for fault identification in optical communication systems
AssigneeTyco Electronics Subsea Communications LLC
InventorsHongbin Zhang, Lee Richardson
Life of this patent
Estimating the term…
Abstract
A system and method for fault identification in optical communication networks. One or more repeaters in the system includes a loop back path that couples an output a first amplifier for amplifying signals carried in a first direction through a repeater to an input of a second amplifier for amplifying signals carried in a second direction through said repeater. Fault analysis is conducted using loop gain data associated with test signals transmitted on the first or second paths and returned on the opposite path through the loop back paths.
Claims12
An optical communication system comprising:
- line monitoring equipment configured to provide a test signal;
- a first optical fiber path configured to receive said test signal and carry said test signal in a first direction;
- a second optical fiber path configured to carry signals in a second direction opposite from said first direction;
- and
- a plurality of repeaters coupled to said first and second optical fiber paths, each of said repeaters comprising,
- a first optical amplifier configured to amplify optical signals on said first optical fiber path,
- a second optical amplifier configured to amplify optical signals on said second optical fiber path, and
- a loop back path coupling an output of said first optical amplifier to an input of said second optical amplifier, said loop back path being configured to couple at least a portion of said test signal to said second optical fiber path as a returned test signal,
- said line monitoring equipment being configured to calculate differential loop gain data associated with each of said loop back paths from said returned test signals of said plurality of repeaters and provide an output identifying a fault in the optical communication system in response to said differential loop gain data, said differential loop gain data comprising, for each one of said loop back paths,
- a loop gain imparted to said test signal through said each one of said loop back paths, minus
- a previous loop back path loop gain imparted to said test signal through one of said loop back paths preceding said each one of said loop back paths.
A method of monitoring an optical communication system comprising a plurality of loop back paths coupling a first optical fiber path for carrying signals in a first direction and a second optical fiber path for carrying signals in a second direction opposite to the first direction, said method comprising:
- transmitting a test signal on the first optical fiber path;
- coupling at least a portion of said test signal from said first optical fiber path to said second optical fiber path through each said loop back path as an associated returned test signal, each said loop back path coupling an output of a first optical amplifier disposed in an associated repeater and configured to amplify signals on said first optical fiber path to an input of a second amplifier disposed in said associated repeater and configured to amplify signals on said second optical fiber path;
- receiving said returned test signals from each of said loop back paths from the second optical fiber path;
- calculating differential loop gain data associated with each of said loop back paths from the returned test signals;
- and
- identifying a fault in the optical communication system in response to said differential loop gain data, said differential loop gain data comprising, for each one of said loop back paths,
- a loop gain imparted to said test signal through said each one of said loop back paths, minus
- a previous loop back path loop gain imparted to said test signal through one of said loop back paths preceding said each one of said loop back paths,
- wherein each of said plurality of repeaters comprises a second loop back path, and wherein said method further comprises:
- transmitting a second test signal on the second optical fiber path;
- coupling at least a portion of said second test signal from said second optical fiber path to said first optical fiber path through each said second loop back path as an associated second returned test signal, each said second loop back path coupling an output of said second optical amplifier to an input of said first optical amplifier;
- receiving said second returned test signals from each of said second loop back paths from the first optical fiber path;
- calculating second differential loop gain data associated with each of said second loop back paths from said second returned test signals;
- and
- identifying whether said fault is in said first or second optical fiber path in response to said differential loop gain data and said second differential loop gain data.
Dependencies are inferred from the claim text.